A power gas circuit breaker provided in a transformer station or a switching station employs a spring operation apparatus employing a spring as driving force for interrupting or closing. A circuit breaker employing this kind of spring operation apparatus is disclosed in JP 2001-283691 A (document 1), for instance. This publication discloses closing of a make and break contact which is an interruption part by releasing an energized state on the base of a cam mounted on a rotation shaft, a lever and an operation command, and an operation apparatus of spring operation type using an interruption spring, etc. This spring operation apparatus does an interruption operation by holding a driving force of the interruption spring by engagement of a plurality of parts constructing a pull-out mechanism, and by releasing the engagement of the plurality of parts by driving a solenoid according to an interruption command.
Further, a spring operation apparatus for opening and closing a contact portion of a power circuit breaker is also disclosed in JP 2005-209554 A (document 2). This spring operation apparatus is made so as to add a case containing a pull-out mechanism or a closing mechanism to a case of a body of the operation apparatus.
Further, a spring operation apparatus by a torsion bar is disclosed in Japanese patent publication No. 2529264 (document 3). This spring operation apparatus uses the torsion bar for driving force of interruption and closing, and it is made compact and its high speed operation is made possible, by using the bar in a state that 2 torsion bars are folded.
Further, Japanese Heisei 9 year (1997) Electro-technical Committees Energy Branch Meeting Lecture Papers “Development of 362 kV 50 kA spring operation gas circuit breaker” by Haruhiko Kayama and others (document 4) also discloses an example of a torsion-bar type spring operation gas circuit breaker. The spring operation apparatus employed therein uses a torsion bar as a driving spring, whereby less energy is needed for driving the spring itself, the efficiency is good, it is possible to it large in output, and the make and break contact which is an interruption portion can be interrupted in an interruption time of 2 cycles.
Incidentally, the spring operation apparatus for circuit breaker as mentioned in the document 1 is for 3-cycle interruption, the document 1 does not take into consideration about designing and manufacturing circuit breakers satisfying a plurality of different interruption speeds such as high speed interruption, for example, interrupting the make and break contact of an interruption portion in 2 cycle, and low speed interruption, for example, interrupting in 5 cycles. The spring operation apparatus for circuit breaker disclosed in above-mentioned document 2 has a problem that it is difficult to meet the requirement of making the circuit breaker high in interruption speed.
Similarly, the torsion-bar type spring operation apparatus disclosed in the document 3 can interrupt a make and break contact which is an interruption portion in 2 cycles, however, it is not taken into consideration about using the spring operation apparatus for low speed interruption such as 3 cycles, so that it has a problem that it can not be used for low speed interruption.
In the other words, the conventional techniques of spring operation apparatuses used for circuit breakers never take into consideration about making parts of the spring operation apparatus common or standardize so as to able to make a make and break contact which is a interruption portion interrupt in different interruption cycles, so that there remains a problem that designing and manufacturing of the circuit breakers becomes complicated.
An object of the present invention is to reduce working time of designing and manufacturing circuit breakers of different interruption speeds, by making it possible to satisfy, even if different interruption speeds are required for circuit breakers of the same construction, the requirement, and by making parts of the spring operation apparatuses common or standardize.